Prescription for a Healthy Lawn: Aerate and Amend with Lime or Gypsum

If your lawn isn’t lush or weeds are taking over, it’s not your fault. Your soil may be too acidic. In regions with acidic soil, nitrogen and other nutrients may be absent. To green up your lawn, lower the pH of the soil by adding lime now.

To learn if your pH is too low (acidic), use a simple soil test kit to find out where it falls in the range of acid to alkaline. (Learn more about testing soil.)

Clay soils and lawns, compacted by too much foot traffic, are common nationwide. Gypsum opens the soil to allow faster drainage for water conservation and increases absorption rates of fertilizer. If you are applying only gypsum for non-acidic soils to open them up, do it now.

Lime and gypsum work best when applied over a freshly aerated lawn where the granules can settle into the small holes made by the aeration machine. This helps lime and gypsum reach the grass roots. (See how to aerate.)

It’s important to apply lime to a very dry lawn, so it doesn’t burn the grass. Lime can burn living grass when it sticks to damp grass blades instead of filtering down to the soil.

How to Apply Lime and/or Gypsum to your Lawn:

Calculate how much product you need by first measuring your lawn. Multiply length times width in feet to yield overall square footage.

Next, divide square footage by 1,000 and multiply the total by number of pounds per square foot. Gypsum is applied at 40-50 pounds per 1,000 square feet. Lime is applied at 20-30 pounds per 1,000 square feet, or ask your Garden Center associate for assistance.

If using both, mix gypsum and lime together in a wheelbarrow and then fill the spreader. Otherwise, just fill your spreader with either lime or gypsum.

Set the spreader to the delivery rate designated on the amendment packages.

Begin with a dry lawn and make passes back and forth in a single direction.

Make a second round of passes perpendicular to the first for uniform coverage.

Water the lawn generously to work the material down to the soil and keep it off the grass blades.